Invented by Felix Wankel, the rotary engine found greatest fame and success through Mazda, but before the Japanese manufacturer put it into widescale production, particularly in the United States, it felt the need to explain how a rotary engine worked and how it differed from the conventional reciprocating piston engine. The resulting video (uploaded to YouTube by djphilmanns) was released in the late 1960s and takes a thorough look at the basics of rotary engine operation.

“Proper care” is the correct term. If you ever let a rotary engine overheat, it is ruined. My first car was a 1973 Mazda RX-2 coupe. It was bright orange and my mother christened it “The Pumpkin” on the day I brought it home, in reference to Cinderella’s magic coach after the clock struck midnight. The engine barely ran. We discovered that it had overheated at some time in the past. We broke the engine down and tried to get it to work, but the aluminum sections of the engine were warped.

Fast-forward 3 years: our neighbor up the road had a wrecking yard and one day I saw him towing in a wrecked RX-2 sedan. 30 minutes and $350 dollars later, I had a parts car with a good engine. I drove the car for about 2 years before loaning it to my sister for the weekend. She let it overheat, even after very careful instructions from me on watching the temp guage. I coulnd’t find another good engine in a wrecking yard and Mazda wanted nearly $2000 for a new engine. My little Pumpkin went to a scrap yard loaded with a lot of other scrap metal where I got about $40 for her.

No, it was never going to be a mainstream replacement for pistons and valves. No worse fuel economy than other sportsters of the era, but Mazda made a tactical error in the early 70s concentrating on the rotary in econoboxes.

Fantastic video. Please keep these coming. I lived with a girl in college who had an 88 or 89 RX-7. It was great fun to drive and we took it on a number of road trips, but it got horrible fuel economy….. so much for the ‘efficiency’ argument; perhaps that only applied to carburetor-equired V8s…

I think the rotory got a bit of a bad rap because most Americans don’t take care of their cars. The first rotory cars & trucks had a manual choke that many Americans had forgotten how to use properly. I know my brother damaged the motor in my Dads truck because he didn’t follow my Dads instructions on using the choke, checking the oil level and watching the engine temp. He ended up washing the oil down with fuel because of leaving the manual choke on; running the engine oil level down because of faster oil consumption and then over heating the rotors because of a lack of engine oil cooling. he then continued to drive it while running hot until it would nolonger start. The apex seals ended up sticking into the rotors and the compression was lost. Another Brother had a different Rotory pickup for years of trouble free driving because he didn’t let his brothers borrow his truck like Dad did.

The AMC Pacer was planned as a Wankel powered car. AMC had a (worthless) contract with GM to supply them with Wankel engines for their new pride and joy.
Historical Note: In its earliest days of introduction the Pacer set sales records, beating such prior sales successes as the Mustang.
Then everyone who thought they wanted one had bought theirs and sales sagged permanently to low levels!

My first new car ever was a 1971 R-100. Fresh out of the Navy and flush with money I bought the car and loved driving it. Interestingly it got better gas mieage around town because until the secondaries of the miniature four barrel opened it was not too thirsty. Could always tell when it needed a tune up – the engine stopped backfiring. Also kept a gallon of 10W40 oil in the trunk to keep the rotor tip seals alive.

2mm apex seal 14mm plug hole when a apex cross the plug hole it leaks all of its comppression stroke into the exh stroke and air and fuel never got used for you on the track please watch on you tube rotary breakyhrough 1 847 421 3592

I worked for Mazda Corporation for nearly 20 years. The Mazda Rotary engine was not considered to be a “Wankel” upon which it was based. It was so vastly improved that the Mazda was just a different engine. Which is why Mazda referred to it with the name, “Rotary.”

And yes, Mazda did miscalculate the market when it attempted to make all of the models it sold in North America only as rotaries. Furthermore, the Japanese never anticipated a situation where owners didn’t bother to change oil or maintain a cooling system. Back then, this was something they just could not envision! Driving conditions and rules there and in North America were just vastly different.

And yes, the early Mazda Rotary engines did indeed suffer from maladies of the apex seals. BUT… to Mazda’s great credit, they took back every one of those early engines and fixed them in their own rebuild facilities–of which there were several in the USA including one on both coasts.

Mazda greatly improved this engine and made it right. The later ones were about as bullet-proof as an aluminum production engine is going to get for now. Ultimately the proof of this was a very durable engine sold in the RX-7 series sports cars and in the RX-08.

But Mazda also was a fierce competitor in racing with this engine. It dominated for many years in its class in racing. It was light, small and had amazing power for its size.

These engines were all 2-rotors. I drove a prototype 3-rotor and I can tell you, the power out of that thing was like a VERY strong V-8, but much smoother. With a turbo, it was downright frightening!

While the Mazda Rotary engine is recently discontinued for sale in the USA, last I knew it continues to be sold overseas.

As for aluminum engines of any sort becoming toast from overheating, this is just a known fact that is hardly restricted to the Mazda Rotary. A friend with a conventional GM aluminum engine just allowed her kid to go hot-rod with her car and an ill-maintained marginal cooling system. Guess what? It came back with… ta-dahhh! … a blown head gasket. Find me an old Cadillac Northstar (as wonderful as that engine is) with a poorly maintained cooling system and oil that has not been changed regularly and I’ll bet it has a blown head gasket. Watch for them on eBay if you are skeptical and see how many are listed for sale with a blown head gasket.

All of the wonderful positive aspects of these Mazda Rotary engines are so easily overlooked today. And all of the very hard years of work by Mazda engineers to make these engines reliable almost never get mentioned. But the negative issues and rumors of the early rotary engines–real or not–go on and on. Yes, the engines get a bad rap and they just don’t deserve it. But it is what it is.

By the way, there was once a very nice, large electrically-motorized cutaway Mazda Rotary display engine that was donated to the Briggs Cunningham Automotive Museum in Costa Mesa, CA. There was a rumor that this display went to Miles Collier’s museum in Florida, but then I lost track of it. More recent rumor has it that the display was to be auctioned off. Anybody know where it is now?

Well said! I loved my RX-2 and would love to find another one. I am very familiar with the advantages and disadvantages of the rotary engine and I followed its development over the years through the end of RX-8 availability in the USA.

An article I read said that Mazda was stopping production of the rotary engine, but I realize that could have been the author’s misinterpretation of the facts. Mazda would have to keep producing the rotary for several years to keep the existing car owners supplied with parts and replacement engines.

I’ve a 1985 RX-7 GS that I’ve had since new and never had any major problems with it. It now has over 200,000 miles and seems willing to go on. The gas mileage could be better at around 21 mpg and it does have its quirks, such as it is difficult to start if allowed to sit for an extended time, but the vehicle is durable. The oil filter sits on top of the engine so changing the oil is easy. Everything else service wise is pretty straight forward except the four barrel carb which requires a comprehensive study of the service manual for adjustments. These cars are forgotten gems and one day will be given the positive recognition they rightfully deserve